OPEN END MASONRY FIREPLACE 



ADAPTATION TO LOCATION AND USE 



The open ends may provide a better draft in 

 locations where the prevaiUng winds are in 

 opposite directions in the morning and in the 

 evening, and may further vary during the day. 

 This type is ordinarily used with a grate. A 

 solid plate, attached to the stonework by a 

 chain could, when not used as a cooking top, 

 be set up against one end of the fireplace to 

 control the draft. It is excellently adapted for 

 use on large open picnic areas because it is 

 low and not conspicuous. The disadvantage of 

 this type is that a strong current of air will scat- 

 ter the sparks and create a definite fire hazard. 



DESIGN AND CONSTRUCTION 



The stonework on the sides should be informal 

 and rustic so far as the available material wall 

 allow, and should conceal the fire-clay brick 

 lining and soften the general appearance. 



A "floating pad foundation", reinforced as 

 shown in the dravnngs, consisting of a concrete 

 slab, the top of which is placed slightly below 

 ground level, is reguired. This type of founda- 

 tion will heave and settle under frost action 

 without damaging the stone masonry super- 

 structure. It is not essential in this type of fire- 

 place to carry the foundation walls below the 

 frost line. 



The hearth of the firebox is slightly (1 to 2 

 inches) above the ground level and may be 

 constructed of porous soil, mineral earth, or 

 fire-clay brick. The hearth should be raised 

 in the middle and pitched towards either end 

 in order to provide proper drainage. 



The open-ended firebox (approximating 10 

 inches in height) will accommodate longer 

 lengths of wood than the three sided type (pi. 

 III). This firebox should be Uned with fire-clay 

 brick and in the absence of any connecting end 



to bond the sides together, provision should be 

 made to bond the fire-clay brick into the stone 

 masonry walls by the use of headers as shown 

 in figure 3 of this plate. The four courses of 

 fire-clay brick laid on their natural bed vnll 

 slightly exceed 10 inches in height, while two 

 courses laid edgewise will slightly exceed 9 

 inches in height. 



A type of stone should be selected which will 

 resist heat. The width of the stone sides should 

 be kept to minimum dimensions, approximating 

 from 6 to 10 inches. Any standard type of 

 grate may be used. The grate showm is hinged 

 on "\-inch "I" bolts set into the joints, as 

 shown on plate XXII, figure 1. 



Some park authorities have experimented 

 with the open-end fireplace constructed with 

 concrete sides, and with the bars embedded 

 solidly in the concrete walls. In every instance, 

 the expansion of the iron has caused the con- 

 crete to break. 



VARIATIONS IN DESIGN 



A movable grate, securely attached to the 

 stonework (pi. VII) may be substituted for the 

 hinged grate shown in this drawing. 



The stonework in the side walls may be kept 

 at the elevation of the top of the fire-clay 

 brick, if a movable plate or grate is used, in 

 order to regulate heating of dishes and utensils 

 by placing them partly on the grate or plate 

 and partly on the side walls. This method of 

 construction would weaken the bond between 

 the fire-clay brick and the stonework. 



The brick hearth may be omitted and a fill 

 of sand or of mineral earth may be used in 

 its place. If such construction is adopted, then 

 the foundation under each side wall should be 

 carried below the frost line (in lieu of a rein- 

 forced concrete pad). 



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